Replace $.Deferred with ES2015 promises

spec/bookmarks.js

@@ -430,8 +430,13 @@
                                         'jid': 'another@conference.shakespeare.lit'
                                     }).c('nick').t('JC').up().up();
                 _converse.connection._dataRecv(test_utils.createRequest(stanza));
+
+                test_utils.waitUntil(function () {
+                    return $('#chatrooms dl.bookmarks dd').length;
+                }, 300).then(function () {
                     expect($('#chatrooms dl.bookmarks dd').length).toBe(3);
                     done();
+                });
             }));
 
             it("remembers the toggle state of the bookmarks list", mock.initConverseWithPromises(
@@ -472,6 +477,10 @@
                     'nick': ''
                 });
                 test_utils.openControlBox().openRoomsPanel(_converse);
+
+                test_utils.waitUntil(function () {
+                    return $('#chatrooms dl.bookmarks dd:visible').length;
+                }, 300).then(function () {
                     expect($('#chatrooms dl.bookmarks dd:visible').length).toBe(1);
                     expect(_converse.bookmarksview.list_model.get('toggle-state')).toBe(_converse.OPENED);
                     $('#chatrooms .bookmarks-toggle').click();
@@ -481,6 +490,7 @@
                     expect($('#chatrooms dl.bookmarks dd:visible').length).toBe(1);
                     expect(_converse.bookmarksview.list_model.get('toggle-state')).toBe(_converse.OPENED);
                     done();
+                });
             }));
         });
     });

src/converse-bookmarks.js

@@ -229,8 +229,7 @@
                 },
 
                 fetchBookmarks () {
-                    const deferred = new $.Deferred();
+                    const deferred = utils.getWrappedPromise();
-                    const promise = deferred.promise();
                     if (this.browserStorage.records.length > 0) {
                         this.fetch({
                             'success': _.bind(this.onCachedBookmarksFetched, this, deferred),
@@ -245,7 +244,7 @@
                     } else {
                         deferred.resolve();
                     }
-                    return promise;
+                    return deferred.promise;
                 },
 
                 onCachedBookmarksFetched (deferred) {
@@ -482,7 +481,7 @@
                     return;
                 }
                 _converse.bookmarks = new _converse.Bookmarks();
-                _converse.bookmarks.fetchBookmarks().always(function () {
+                _converse.bookmarks.fetchBookmarks().then(function () {
                     _converse.bookmarksview = new _converse.BookmarksView(
                         {'model': _converse.bookmarks}
                     );

src/utils.js

@@ -69,22 +69,22 @@
     };
 
     var isImage = function (url) {
-        var deferred = new $.Deferred();
+        return new Promise((resolve, reject) => {
             var img = new Image();
             var timer = window.setTimeout(function () {
-            deferred.reject();
+                reject(new Error("Could not determine whether it's an image"));
                 img = null;
             }, 3000);
             img.onerror = img.onabort = function () {
                 clearTimeout(timer);
-            deferred.reject();
+                reject(new Error("Could not determine whether it's an image"));
             };
             img.onload = function () {
                 clearTimeout(timer);
-            deferred.resolve(img);
+                resolve(img);
             };
             img.src = url;
-        return deferred.promise();
+        });
     };
 
     $.fn.hasScrollBar = function() {